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Circuit/System Testing

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  1. Verify fuse F23 is not open, Fuse Block - Underhood.
    • If the fuse is open 

      Test the Ignition 1 voltage circuit and all components connected to the Ignition 1 circuit for a short to ground.

    • Go to next step: If the fuse is not open 
  2. Ignition OFF, disconnect the harness connector at the B14A Output Shaft Speed Sensor.
    3. NOTE:
    • Testing for steps 3 - 6 is performed on the B14A Output Shaft Speed Sensor harness connector using the GY probes J-35616-2A.
    • Chassis ground to battery ground 25 - 35 Ω.
  3. Test for less than 10 Ω between the low reference circuit terminal 1 and chassis ground or test for less than 50 Ω if between the low reference circuit terminal 1 and the battery ground.
    • If 10 Ω or greater 

      Repair the open/high resistance in the circuit

    • Go to next step: If less than 10 Ω 
  4. Ignition ON. Engine OFF.
  5. Using a fused jumper wire, test for B+ (+0.0/-0.5 V) between the Ignition 1 Voltage circuit terminal 3 and the low reference circuit terminal 1.
    • If less than B+ (+0.0/-0.5 V) 

      Repair the open/high resistance in the circuit

    • Go to next step: If B+ (+0.0/-0.5 V) 
  6. Test for B+ (+0.0/-2.5 V) between the sensor signal circuit terminal 2 and the low reference terminal 1.
    • If less than B+ (+0.0/-2.5 V) 
    1. Ignition OFF, disconnect the X2 harness connector at the K71 Transmission Control Module.
    2. Test for less than 10 Ω in the sensor signal circuit end to end.
      • If 10 Ω or greater, repair the open/high resistance in the circuit.
      • Go to next step: If less than 10 Ω.
    3. Test for infinite resistance between the sensor signal circuit, terminal 2 and ground.
      • If less than infinite resistance, repair the short to ground in the circuit.
      • Go to next step: If infinite resistance
    4. Test for infinite resistance between the sensor signal circuit terminal 2 and all other terminals of the B14A Output Shaft Speed Sensor harness connector.
      • If less than infinite resistance, repair the short together in the affected circuits.
      • Go to next step: If infinite resistance
    5. Connect the red lead of the J-38522  variable signal generator to the sensor signal circuit terminal 2. Connect the black lead of the J-38522  variable signal generator to the low reference circuit terminal 1. Plug the power cord of the J-38522  variable signal generator into the cigar lighter.
    6. Set the J-38522  variable signal generator to 12 volts, the Frequency to 300, and the Duty Cycle to 50%.
    7. Ignition ON. Verify the scan tool Transmission OSS parameter is between 540 - 660 RPM.
      • If not within the specified range, replace the K71 Transmission Control Module.
      • If within the specified range, test the K71 Transmission Control Module for proper operation. Refer to Component Testing - K71 Transmission Control Module.
    • Go to next step: If B+ (+0.0/-2.5 V) 
  7. Replace the B14A Output Shaft Speed Sensor.
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